When the Rwandan genocide began in April 1994, Eugene Gatari lived near Lake Victoria in neighboring Uganda. He was miles from the slaughter, yet the slaughter came to him.

“Bodies were being thrown into rivers,” he remembered, “and then the bodies were flowing into Lake Victoria.”

After organizing truckloads of food, medicine and other supplies for survivors, Gatari traveled to Rwanda and descended into despair.

“It was a very, very bad moment,” he said. “Even for those who survived, there was no hope.”

Twenty years later, Gatari and other witnesses to this tragedy are in San Diego for an exhibit at the University of San Diego.

“Rwanda, 1994-2014: Seven Photographers,” which opened Thursday and continues through June 6, raises thorny questions about our capacity for violence and forgiveness. While the images explore a horrifying chapter in world history, survivors say the galleries offer glimmers of that elusive quality, hope.

“This is very important,” said Gatari, now a fellow at Harvard’s Kennedy School for Public Policy. “The fact that I can see these pictures shows me that somebody cares.”

“It’s good to remember,” said Dida Nibagwire, a Rwandan actress who lost family members in the genocide. “If people are reminded that this happened, people will learn a lesson from that.”

“Rwanda, 1994-2014: Seven Photographers”

When: Now through June 6; Monday, Tuesday, Wednesday and Friday, noon to 5 p.m.; Thursday, noon to 6 p.m.; closed Saturday and Sunday

Admission: Free

Information: (619) 260-7618

Hanging over the exhibit, though, is a sobering question: Has that lesson been learned well enough?

Philip Lancaster, a retired Canadian colonel who had served with the United Nations peacekeeping force in Rwanda, notes rising ethnic violence in south Sudan and the Central African Republic. Could it happen again?

“It’s already happening,” he said.

‘What happened?’

Many accounts say the Rwandan genocide occurred over 100 days. From April 7 through mid-July 1994, between 500,000 and 1 million people were murdered — most victims were Tutsis, a minority tribe in Rwanda, while most of the killers came from the majority Hutu tribe.

The aftermath, too, has been complicated. Over a 10-year period, more than 2 million people appeared before community tribunals known as gacaca, charged with numerous crimes; 75 appeared before the International Criminal Tribunal for Rwanda, where 47 were convicted.

These hearings, especially the local gacaca sessions, helped bind this society’s wounds. Victims were able to face their tormentors and tell their tales.

“Significant progress was made in dealing out justice,” said Daniel Bekele, an Ethiopian who directs Human Rights Watch’s Africa Division. “But there are still a number of perpetrators at large.”

Some of those took shelter in nearby countries, where they have raised troops and launched attacks on camps that harbor uprooted Rwandans. This in turn prompted the new Rwandan government to send troops into Zaire, slaughtering suspected collaborators.

“The people involved had held back revenge for so long,” Lancaster said, “at a certain point they lost control.”

Vengeance, though, has been surprisingly rare.

“The level of forgiveness that people show — that’s just taught me so much about human nature,” said Paige Stoyer, one of the photographers whose work is shown here. “People live next to perpetrators. I don’t know how they do it.”

One reason so few struck back, in Gatari’s view: conscience.

“We didn’t want to be like that,” he said.

Nibagwire cited another inhibiting factor: shock.

“People were traumatized,” the actress said. “They would ask, ‘What just happened?’ It took time to realize what happened.”

State of shock

Some of this confusion is reflected in the exhibit. In the work of Robert Lyons, Rwandans stare straight at the camera. Some of these people are murderers; others lost loved ones in the bloodbath. Lyons doesn’t tell us which is which, yet all appear haunted.

In the aftermath of the genocide, Rwanda was a haunted land, struggling to reclaim the trappings of normal life.

“You would go into little settlements and find one or two people walking around in a state of shock,” Lancaster said. “And yet at the end of September, you would find schools open and children attending, even if there were no teachers.”

After fleeing her native land to save her life, Nibagwire was also eager for peace and its mundane routines. Returned to Rwanda, she founded a drama troupe in 2006. On stage, Art For Peace regularly explores the theme of reconciliation. Offstage, the director found herself responsible for — and responsive to — people from varied backgrounds.

“That’s where I started thinking outside myself,” Nibagwire said. “What about this boy who has both parents in prison for life? Because of what they did, other people see him as a killer.”

Not Nibagwire, whose company welcomes such children.

Her country faces challenges, she said, and there’s still tensions and misunderstandings. But there’s something else: hope that Rwanda can move beyond its tragic past.

“I talk to people,” she said, “and they feel, after 20 years, yes, we can do it.”